Flavoring and fragrance compositions

ABSTRACT

PROCESSES FOR ALTERING THE FLAVORS AND AROMAS OF CONSUMABLE PORDUCTS, INCLUDING FOODSTUFFS AND TOBACCOS, WHICH COMPRISE ADDING THERETO A SMALL BT EFFECTIVE AMOUNT OF AT LEAST ONE TRICYCLIC PYAZINE HAVING THE FORMULA   2,3-(-(CH2)M(-R1)(-R2)(-R7)(-R8)-),5,6-(-(CH2)M(-R3)(-R4)   (-R5)(-R6)-)PYRAZINE   WHEREIN M AND N ARE EACH AN INTEGER FROM 1 TO 6, AND R1, R2, R3, R4, R5, R6, R7 AND R8, ARE THE SAME OR DIFFERENT AND REPRESENT HYDROGEN OR ALKYL; THE PRODUCTS SO PRODUCED; FLAVORING AND FRAGRANCE COMPOSITIONS CONTAINING SUCH TRICYCLIC YAZINES; AND CERTAIN NOVEL PYRAZINES AND PROCESS FOR THEIR PRODUCTION.

United States Patent Office 31,705,121 Patented Dec. 5, 1972 ABSTRACT UPTHE DISCLOSURE Processes for altering the flavors and aromas ofconsumable products, including foodstuffs and tobaccos, which compriseadding thereto a small but effective amount of at least one tricyclicpyrazine having the formula wherein m and n are each an integer from .1to 6, and R R R R R R R and R are the same or different and representhydrogen or alkyl; the products so produced; flavoring and fragrancecompositions containing such tricyclic pyrazines; and certain novelpyrazines and processes for their production.

(CHz) BACKGROUND OF THE INVENTION The present invention relates totricyclic pyrazines and their use in processes and compositions foraltering the flavors and aromas of various materials such as tobaccos,foodstuffs, and the like, as well as certain novel pyrazines andprocesses for producing them.

Because of the tremendous consumption of foods, tobaccos, and othermaterials, there has been an increasing interest in substances andmethods for imparting flavors to such consumable materials. Thisinterest has been stimulated not only because of the inadequate quantityof natural flavoring materials available, but perhaps even moreimportantly, because of the need for materials which can convey certainnuances, will be more stable than natural materials, will blend betterwith other flavors or flavoring composition components, and willgenerally provide superior products.

There have recently been suggestions that certain pyrazine derivativeshave flavors which might be useful in foods and other consumablematerials. For example, tetramethylpyrazine has been suggested for usewith vanillin in chocolate flavors, acetylpyrazine has been used intobacco and foods, and methoxypyrazine has been said to impart anut-like flavor to foods. Pyrazino- [b1'cyclopentanes have also beensuggested.

THE INVENTION It has now been found that certain tricyclic pyrazines arecapable of imparting a wide variety of flavors and fragrances to variousconsumable materials. Briefly, the invention contemplates altering theflavors and/or fragrances of such consumable materials by adding theretoa small but effective amount of at least one tricyclic pyrazine havingthe formula RE R2 R4 wherein m and n are each an integer from 1 to 6,in-

elusive; and R R R R R R R and R represent hydrogen or alkyl and are thesame or different. The invention also contemplates flavoring andfragrance compositions containing such tricyclic pyrazines.

More specifically, the tricyclic pyrazines according to this inventionare pyrazines to the b and e sides of which are fused five toten-membered hydrocrabon rings. Such rings can be substituted with oneor more alkyl groups. In some instances one or the other of the ringscan be substituted with an alkadienyl group. It will be appreciated fromthe present disclosure by those skilled in the art that one or morepairs of the alkyl groups 'substituent on the hydrocarbon ring can begeminal, i.e., can be attached to the same ring carbon atom. It isgenerally preferred in practicing the present invention that thesubstituents be hydrogen or a lower alkyl group, particularly one havingfrom one to three carbon atoms.

A tricyclic pyrazine for use herein is 1,2,3,4,5,6,7,-8,9,-octahydrophenazine having the formula This yellowish viscous liquid hasfried corn chip odor and flavor characteristics, as further describedhereinafter.

Another tricyclic pyrazine according to this invention is1-methyl-2,3,5,6-,7,'8 hexah'ydro-1(H)-cyc1openta-[b] quinoxaline havingthe formula (Iii) This substance is a pale yellowish liquid having anutlike aroma.

A further tricyclic pyrazine used herein is the novel material 1,2,3,4,6,7,8,9,10,11,12,13-dodecahydrocyclodeca[b] quinoxaline having theformula This oily material has a light, sweet nut flavor and aromacharacter.

The following intermediates are particularly useful in the preparationof the various tricyclic pyrazines:

l-methyl 3,4a,5,6,7,8,-8a,9 octahydro 2(H)-cycloepnta- [b] quinoxaline1,2,3,4,4a,6,7,8,9,10a-decahydrophenazine;

are

1,2,3,4,4a,5,7,8,9,10,l1,12,13,14a tetradecahydrocyclodeca [b]quinoxaline;

1,2,3,4,4a,6,7,8,9,l0,11,12,13,14atetradecahydrocyclodeca[b]quinoxaline; and1,2,3,4,4a,6,7,8,9,9a-decahydrophenazine It will accordingly beappreciated that the present invention also provides novel asymmetrictricyclic pyrazines having the formula R1 R Ra Ra wherein m and n aredifferent integers from one to six, inclusive; two or three of thedashed lines represent nonallenic double bonds; and R R R R R R R and Rare hydrogen or lower alkyl. When alkyl groups are present in thesetricyclic pyrazines or tricyclic dihydropyrazines, they are preferablylower alkyl having from one to three carbon atoms.

The tricyclic pyrazines prepared according to the present invention canbe obtained by a number of reaction routes, as by reacting a1,2-diaminocycloalkane or monoalkylor polyalkyl-substituted1,2-diaminocycloalkane with a 1,2-cycloalkanedione or monoalkylorpolyalkyl-substituted derivatives thereof under ring-closing conditionsor by reacting such 1,2-diaminocycloalkanes or derivatives with a1,2-cycloalkanedione or monoalkylor polyalkyl-substituted derivativesthereof, followed by aromatization of the heterocyclic ring, or with aZ-halocycloalkanone or monoalkylor polyalkylsubstituted deriavtivesthereof; or by reacting a 2-aminocycloalkanone or monoalkylorpolyalkyl-substituted derivatives thereof with a like or a different2-aminocycloalkanone. The reactants are preferably utilized instoichiometric proportions. The tricyclic dihydropyrazine compoundsobtained upon ring-closure are then dehydrogenated as desired to providethe fused pyrazine ring.

It will accordingly be appreciated by those skilled in the art that when1,2-diaminocyclopentane and 1,2-cyclopentanedione are reacted, m and nin the generic formula will both be one, while when 1,2-cyclodecadioneand 1,2-diaminocyclopentane are reacted m will be six and n will be one.Similar results will follow from the other reactions set forth aboveutilizing reactants having from five to ten carbon atoms in each ring.

The reaction can accordingly be represented as one between a cyclicketone having the formula and a cyclic amine having the formula Ra RaHZNI X DD Y 1% oxygen; except that X and Y cannot both be amino or bothbe carbonyl oxygen and X cannot be a halo atom when Y is carbonyloxygen; and wherein R R R R R R R and R are the same or different andare hydrogen or lower alkyl. Thus, X and Y taken together is one of thefollowing pairs of groups:

( 1) Carbonyl oxygen Amino. (2) Halo atom Do. (3) Amino Halo atom. (4)Amino Carbonyl oxygen.

Examples of the 1,2-diaminocycloalkanes which can be used herein are:

Examples of the 2-halo-cycloalkanones are:

2-chlorocyclohexanone;

2-bromocyclohexan0ne;

2-chloro-3 ,4-dimethylcyclohexanone;2-chl0ro-3,3,5,5-tetramethylcyclohexanone; 2-bromocycloheptanone;2-bromo-3,4,5-triethylcycloheptanone;2-bromo-3,4,5,6-tetramethylcycloheptanone; and2-chloro-5-methylcyclodecanone Examples of the 1,2-cycloa'lkadionescapable of being utilized herein are:

B-methyl-1,2-cyclopentadione; 1,2-cyclodecadione;4,4-dimethyl-1,2-cyclodecadione; 3,7 -diethyll ,2-cyclononadione; 3,4,5-trimethyl-7ethyl-1 ,2-cyclononadione 1,2-cyclonondione;1,2-cyclooctadione; 3-methyl-1,2-cyclohexadione;4-methyl-1,2-cycloheptadione; 1,2-cycloheptadione; and1,2-cyclopentadione.

Examples of amino cycloalkanones capable of being utilized herein are:

2-aminocyclopentanone-l; Z-aminocyclohexanone-l; 2-aminocycloheptanone-1; 2-aminocyclooctanone- 1; 2-aminocyclodecanone-1;2-amino-4-methylcyclononanone-1 2-amino-3,3-dimethylcyclopentanone-1;and 2-amino-3-methy1-4-ethylcyclohexanone-1.

The reaction of the diamine and diketone is carried out at a temperatureof from 0 C. At temperatures lower than 0 C., the reaction rate isrelatively slow, while at temperatures higher than about 100 C., thereactants tend to polymerize. It is preferred to carry the reaction outat temperatures of from C. to C. The time for the reaction to form thetricyclic pyrazine is from about one hour up to eight hours. It isdesirable to conduct the reaction so that the time required is fromabout two to about four hours.

In order to promote a more uniform reaction by moderating the rate andproviding good mixing and to facilitate removal by azeotropicdistillation of the water formed in the reaction, it is desirable insome aspects of the invention to utilize a liquid reaction vehicle. Thevehicle is desirably a solvent for the reactants and any otheringredients which are present in the reaction mixture and forms anazeotrope with water. The vehicle can also be chosen so that the refluxtemperature of the reaction mixture is within the temperature ranges ashereinbefore set forth. Thus, the preferred reaction vehicles utilizedat reaction temperatures above 15 C. include aromatic hydrocarbons suchas benzene, toluene, xylene, and the like. Vehicles which can beutilized at lower reaction temperatures of to -15 C. include aliphaticalcohols such as methanol, ethanol, isopropanol, and the like andaliphatic and alicyclic ethers such as tetrahydrofuran, diethyl ether,and the like. It will be understood that the alcohols can also be usedat temperatures of C. and above.

The reaction is desirably carried out in the presence of a catalyst topromote the ring-closing reaction and form the reduced pyrazine ring.The catalysts are generally acid substances, particularly aryl sulfonicacids such as paratoluene sulfonic acid and the like. Based upon thequantity of reactants, it is desirable to use from about 0.5 to aboutfive percent of such catalysts. All parts, proportions, percentages, andratios herein are by weight unless otherwise indicated.

After the formation of the reduced tricyclic pyrazine, it is oxidized toprovide the corresponding pyrazine derivative. This is carried out at analkaline pH obtained by adding a strong alkali metal hydroxide or anequivalent material such as alkali metal carbonate. The hydroxides ofsodium or potassium are desirably used.

The hydroxide-containing mixture is then treated with oxygen at atemperature of from to 70 C. to provide a satisfacory reaction ratewhile minimizing undesirable side reactions and the ebullition of thereactants. The oxygen can be pure or can contain inert diluents. Air canbe used as the oxygen source.

The oxygen is added to the reactants by sparging or otherwise bubblingthe gas through the reaction mixture. At the temperatures used herein,the times for the reaction range from about 30 minutes to 24 hours, andit is desirable to carry out the reaction so that it attains a highdegree of completion in from about one to five hours.

The oxidation reaction is desirably carried out in an inert reactionvehicle to reduce polymer formation, to permit better control over thereaction temperature, and to improve mixing of the reactants. Thepreferred inert reaction vehicles are solvents and include alkanols,preferably lower alkanols such as methanol, ethanol and the like.

After the reaction is complete, as readily determined by gaschromatography, the pH of the reaction mixture can, if desired, bereduced by the addition of an acid, desirably a strong mineral acid suchas dilute sulfuric acid, preferably 10% to 50% sulfuric acid. If anyundissolved hydroxide exists at this point then it is preferred that itbe removed, as by centrifugation or filtration. The crude tricyclicpyrazine is then stripped of vehicle and further purified as desiredaccording to the procedures hereinafter described.

It will be understood by those skilled in the art that the intermediateand the final products prepared herein are washed and dried to obtainthe desired substances. The novel tricyclic pyrazines can be obtained inpurer form or in substantially pure form by conventional purificationtechniques. Thus, the products can be purified and/or isolated bydistillation, extraction, crystallization, preparative chromatographictechniques, and the like. It has been found desirable to purify thetricyclic pyrazines =by fractional distillation under vacuum.

It will be appreciated from the present disclosure that the tricyclicpyrazines and mixtures thereof according to the present invention can beused to alter, vary, fortify,

6 modify, enhance, or otherwise improve the flavor of a wide variety ofmaterials which are ingested, consumed, or otherwise organolepticallysensed.

The term alter in its various forms Will be understood herein to meanthe supplying or imparting a flavor character or note to an otherwisebland, relatively tasteless substance, or augmenting an existing flavorcharacteristic where the natural flavor is deficient in some regard, orsupplementing the existing flavor impression to modify organolepticcharacter.

Such pyrazines are accordingly useful in flavoring compositions. Aflavoring composition is taken to mean one which contributes a part ofthe overall flavor impression by supplementing or fortifying a naturalor artificial flavor in a material or one which supplies substantiallyall the flavor and/or aroma character to a consumable article.

The term foodstuff as used herein includes both solid and liquidingestible materials for man or animals, which materials usually do, butneed not, have nutritional value. Thus, foodstuffs includes meats,gravies, soups, convenience foods, malt, alcoholic, and other beverages,milk and dairy products, seafoods including fish, crustaceans, mollusks,and the like, candies, vegetables, cereals, soft drinks, snacks, dog andeat foods, other veterinary products, and the like.

The term tobacco will be understood herein to mean natural products suchas, for example, burley, Turkish tobacco, Maryland tobacco, flue-curedtobacco and the like including tobacco-like or tobacco-based productssuch as reconstituted or homogenized leaf and the like, as well astobacco substitutes intended to replace natural tobacco, such as lettuceand cabbage leaves and the like. The tobaccos and tobacco productsinclude those designed or used for smoking such as in cigarette, cigar,and pipe tobacco, as well as products such as snuff, chewing tobacco,and the like.

When the tricyclic pyrazines of this invention are used in a flavoringcomposition, they can be combined with conventional flavoring materialsor adjuvants. Such co-ingredients or flavoring adjuvants are well knownin the art for such use and have been extensively described in theliterature. Apart from the requirement that any such adjuvant materialbe ingestibly acceptable, and thus non-toxic or otherwisenon-deleterious, conventional materials can be used and broadly includeother flavor materials, vehicles, stabilizers, thickeners, surfaceactive agents, conditioners, and flavor intensifiers.

Such conventional flavoring materials include saturated, unsaturated,and amino acids; alcohols, including primary and secondary alcohols;esters; carbonyl compounds including ketones and aldehydes; lactones;other cyclic organic materials including benzene derivatives,alicyclics, heterocyclics such as furans, pyridines, other pyrazines andthe like; sulfur-containing materials including thiols, sulfides,disulfides and the like; proteins; lipids; carbohydrates; so-calledflavor potentiators such as monosodium glutamate, guanylates, andinosinates; natural flavoring materials such as cocoa, vanilla, andcaramel; essential oils and extracts such as anise oil; clove oil, andthe like; artificial flavoring materials such as vanillin; and the like.

Stabilizers include preservatives such as sodium chloride, and the like,antioxidants such as calcium and sodium ascorbate, ascorbic acid,butylated hydroxyanisole, butylated hydroxytoluene, propyl gallate andthe like, sequestrants such as citric acid, EDTA, phosphates, and thelike.

Thickeners include carriers, binders, protective colloids, suspendingagents, emulsifiers and the like, such as agaragar, carrageenan,cellulose and cellulose derivatives such as carboxymethyl cellulose andmethyl cellulose, natural and synthetic gum such as gum arabic, gumtragacanth, and the like, and other proteinaceous materials, lipids,carbohydrates, starches, and pectins.

Surface active agents include emulsifying agents such as monoand/ ordiglycerides of fatty acids such as capric acid, caprylic acid, palmiticacid, myristic acid, stearic acid, oleic acid, and the like, lecithin,defoaming and flavor-dispersing agents such as sorbitan monostearate,pitassium stearate, hydrogenated tallow alcohol, and the Conditionersinclude compounds such as bleaching and maturing agents such as benzoylperoxide, calcium peroxide, hydrogen peroxide and the like; starchmodifiers such as peracetic acid, sodium chlorite, sodium hypochlo rite,propylene oxide, succinic anhydride and the like, buffers andneutralizing agents such as sodium acetate, ammonium bicarbonate,ammonium phosphate, citric acid, lactic acid, vinegar and the like;colorants such as carminic acid, cochineal, turmeric, curcumin and thelike; firming agents such as aluminum sodium sulfate, calcium chlorideand calcium gluconate; texturizers; anti-caking agents such as aluminumcalcium sulfate and tribasic calcium phosphate; enzymes; yeast foodssuch as calcium lactate and calcium sulfate; nutrient supplements suchas iron salts such as ferric pyrophosphate, ferrous gluconate and thelike, riboflavin, vitamins, zinc sources such as zinc chloride, zincsulfate, and the like.

The tricyclic pyrazines, or the compositions incorporating them, asmentioned above, can be combined with one or more vehicles or carriersfor adding them to the particular product. Vehicles can be edible orotherwise suitable materials such as ethyl alcohol, propylene glycol,water, and the like. Carriers include materials such as gum arabic,carrageenan, other gums, and the like. The tricyclic pyrazines can beincorporated with the carriers by conventional means such asspray-drying, drum-drying, and the like. Such carriers can also includematerials for coacervating the pyrazines (and other flavoringingredients, as present) to provide encapsulated products. When thecarrier is an emulsion, the flavoring composition can also containemulsifiers such as monoand diglycerides of fatty acids and the like.With these carriers or vehicles the desired physical form of thecomposition can be prepared.

It will be understood by those skilled in the art that the tricyclicpyrazines can be added during production of the finished product. Thus,when the pyrazines are used to alter or otherwise vary the flavor of afoodstufl, they can be added in the original mixture, dough, emulsion,batter, or the like prior to any cooking or heating operation.Alternatively, they can be added at a later stage of processing ifvolatilization losses would be excessive during the earlier processing.

When the materials are used to treat tobacco products, for example, theadditive can be applied in a suitable manner, as by spraying, dipping,or otherwise. The pyrazines can be applied during the casing or finalspray treatment of the tobacco, or they can be applied at some earlierstage of curing or preparation. The quantity of pyrazines or mixturesthereof utilized should be suflicient to impart the desired flavorcharacteristic to the product, but on the other hand, the use of anexcessive amount of the pyrazines is not only wasteful and uneconomicalbut in some instances too large a quantity may unbalance the flavor orother organoleptic property of the product consumed. The quantity usedwill vary depending upon the ultimate foodstuff, tobacco product, orother consumable product; the amount and type of flavor initiallypresent in the product; the further process or treatment steps to whichthe product will be subjected; regional and other preference factors;the type of storage, if any, to which the product will be subjected; andthe pre-consumption treatment, such as baking, frying, and so on, givento the product by the ultimate consumer. Accordingly, the terminologeffective amount and sufficient amount is understood in the context ofthe present invention to be quantitatively adequate to alter the flavorof the foodstuff, tobacco, or other consumable material.

It is preferred that the ultimate compositions contain from about 0.1part per million (p.p.m.) to about 100 p.p.m. of tricyclic pyrazines.More particularly, in food compositions it is desirable to use fromabout 0.1 to about 50 p.p.m. and in certain preferred embodiments of theinvention, from about 1 to about 15 p.p.m. of the pyrazines are includedin the finished product. On the other hand, tobacco compositions cancontain as little as 0.1 p.p.m. and as much as 100 p.p.m., dependingupon whether a cigarette tobacco, a pipe tobacco, a cigar tobacco, achewing tobacco, or snuff is being prepared.

The amount of tricyclic pyrazine or pyrazines to be utilized in theflavoring composition can be varied over a wide range depending upon aparticular quality to be added to the foodstuff, tobacco, or otherconsumable material. Thus, amounts of one or more tricyclic pyrazinesaccording to the present invention from about 0.1 percent up to orpercent can be incorporated in such compositions. It is generally foundto be desirable to include from about 0.5 to about 25% of the tricyclicpyrazines in such compositions.

The tricyclic pyrazines of this invention are also useful individuallyor in admixtures as fragrances.

They can be used to contribute a fatty, nut-like aroma. As olfactoryagents the tricyclic pyrazines of this invention can be formulated intoor used as components of a perfume composition.

The term perform composition is used herein to mean a mixture of organiccompounds, including, for example, alcohols, aldehydes, ketones,nitriles, esters, and frequently hydrocarbons Which are admixed so thatthe combined odors of the individual components produce a pleasant ordesired fragrance. Such perfume compositions usually contain: (a) themain note or the bouquet or foundation-stone of the composition; (b)modifiers which round-off and accompany the main note; (c) fixativeswhich include odorous substances which lend a particular note to theperfume throughout all stages of evaporation, and substances whichretard evaporation; and (d) top-notes which are usually low-boilingfresh smelling materials.

In perfume compositions the individual component will contribute itsparticular olfactory characteristics, but the overall effect of theperfume composition will be the sum of the effect of each ingredient.Thus, the individual compounds of this invention, or mixtures thereof,can be used to alter the aroma characteristics of a perfume composition,for example, by high-lighting or moderating the olfactory reactioncontributed by another ingredient in the composition.

The amount of the compounds of this invention which will be effective inperfume compositions depends on many factors, including the otheringredients, their amounts, and the effects which are desired. It hasbeen found that perfume compositions containing as little as 2% of thetricyclic pyrazines of this invention, or even less, can be used toimpart a scent to or alter the scent of soaps, cosmetics, and the otherproducts. The amount employed can range up to 50% or higher and willdepend on considerations of cost, nature of the end product, the effectdesired on the finished product and particular fragrance sought.

The tricyclic pyrazines of this invention can be used alone or in aperfume composition as an olfactory component in detergents and soaps;space odorants and deodorants; perfumes; colognes; toilet waters; bathpreparations such as bath oil and bath salts; hair preparations such aslacquers, brilliantines, pomades, and shampoos; cosmetic preparationssuch as creams, deodorants, hand lotions, and sun screens; powders suchas talcs, dusting powders, face powder, and the like. When used as anolfactory component of a perfumed article, as little as 0.01% of one ormore of the tricyclic pyrazines will suffice to impart a nut-like orhoney odor. Generally, no more than 0.5 percent is required.

In addition, the perfume composition can contain a vehicle or carrierfor the tricyclic pyrazines alone or with other ingredients. The vehiclecan be a liquid such as alcohol, glycol, or the like. The carrier can bean absorbent solid such as a gum or components for encapsulating thecomposition.

The following examples are given to illustrate embodiments of theinvention as it is presently preferred to practice it. It will beunderstood that these examples are illustrative, and the invention isnot to be considered as restricted thereto except as indicated in theappended claims.

Example I.Preparation of 1-methyl-2,3,5,6,7,8-hexahydro-1 (H)-cyclopenta [b] quinoxaline A three-liter flask equipped with condenser,stirrer, heater, and Bidwell trap, is charged with the followingingredients. Ingredients: Amount Cyclotene (3 methyl 1,2, cyclopentanedione) g 34.8 1,2 diaminocyclohexane g 34.2 p-Toluene sulfonic acid g 2Anhydrous benzene liters 1.5

The mixture is refluxed at atmospheric pressure for three hours, duringwhich time 12 ml. of water is collected in the Bidwell trap. Thereaction mass is then cooled and the benzene is stripped off at reducedpressure. The 53 grams of solid residue material is then sublimed toobtain 29 grams of 1-methyl-3,4a,5,6,7,8,8a,9- octahydro 2(H)cyclopenta[b]quinoxaline having the structure:

The structure is confirmed by proton magnetic resonance (PMR) analysis.

Ten grams of the material produced above is charged to a one-literflask, together with 38 ml. of ethanol and 2 g. of solid potassiumhydroxide. The reaction mixture is cooled to 20 C., and oxygen isbubbled into the mixture for one hour. The oxygen-saturated reactionmass is then heated to 50 C., and oxygen is again bubbled in for anotherhour, while the reaction mass is maintained at 50 C.

The reaction mass is cooled, the ethanol is stripped off at reducedpressure, and the residue is then extracted with four 150 ml. volumes ofether and washed with 100 ml. of saturated sodium chloride solution.

The ether extract is dried over anhydrous magnesium sulfate and thedried solution is stripped of ether.

The resulting solid material has a nut-like aroma and the followingstructure:

As confirmed by PMR and mass spectral analysis.

Example II.-Preparation of 1,2,3,4,6,7,8,9 octahydrophenazine Atwo-liter flask equipped with condenser, stirrer, and Bidwell trap ischarged with the following ingredients:

Ingredient: Amount Cyclohexane-1,2-dione g 9.65 1,2-diaminocyclohexane g11.4 P-toluene sulfonic acid g 1.0 Benzene, anhydrous liter 1 Thereaction mass is heated at reflux for two hours until 3.6 ml. of wateris collected in the Bidwell trap. The reaction mass is thereupon cooled,and the benzene is stripped 10 from the reaction mass at reducedpressure to obtain 15 grams of 1,2,3,4,4a,6,7,8,9,IOa-decahydrophenazinehaving the structure:

This structure is confirmed by PMR and infrared ,(IR) analyses.

A one-liter flask is charged with 15 g. of the decahydrophenazinedissolved in 300 ml. of ethanol, 4 g. of potassium hydroxide is added,and oxygen is bubbled into the reaction mass for one hour at -20 C. andthen for one hour at 50 C. The reaction mass is cooled, dissolved inwater, and extracted with diethyl ether. The ether extract is evaporatedand the residue is dissolved in 160 ml. of 95% ethanol. Six grams ofpotassium hydroxide are added to the alcoholic solution and the mixtureis refluxed for four hours whereafter the mixture is cooled and theethanol is stripped off to provide a white solid. This solid isextracted with three 150 ml. volumes of diethyl ether, and the etherextract is washed with the saturated sodium chloride solution. The etherextract is dried over anhydrous magnesium sulfate and stripped of ether.The resulting 4 g. is distilled at a temperature in the range of 130 C.and a pressure of 20-25 mm. Hg. NMR, IR and mass spectral analysisconfirm the structure:

The yellowish viscous liquid has the taste of fried corn chips at alevel of 5 ppm. Example III.-Preparation of 1,2,3,4,6,7,8,9,l0,11,12,13-

dodecahydrocyclodeca-[bJquinoxaline A 2-liter reaction vessel equippedwith stirrer, reflux condenser, and Bidwill trap is charged with:

Ingredient: Amount Cyclodecane-1,2-dione g 10 1,2-diaminocycloheaxne g6.6 P-toluene sulfonic acid g 1.5 Benzene, anhydrous liter 1 The mixtureis refluxed for two hours until 25 ml. of water is collected in theBidwell trap. The reaction mass is then cooled and the benzene strippedoff to yield 21 g. of a solid residue. This material is determined bymass spectral analysis and PMR to be the reduced pyrazine having thestructure:

The 21 grams of solid are dissolved in 250 ml. of ethanol in a 1-literflask, 6 grams of potassium hydroxide is added, and the reaction mixtureis refluxed for three hours and then cooled. The ethanol is stripped 01fand the residue dissolved in 100 ml. of saturated sodium chloridesolution. The sodium chloride solution is extracted four times with ml.portions of ether. The extracts are combined and then dried overanhydrous magnesium sulfate. The dried ether extract is stripped ofether. The resulting 21 g. of residue is distilled at a temperature in arange of 166 C. at 2 mm. Hg. PMR, IR and mass spectral analysis showsthat the material is 1,2,3,4,6,7,8,9,10,11,12,13-dodecahydrocyclodeca[b]quinoxaline having the structure:

This material has a light, sweet, nut character.

Example IV A basic cocoa flavor material is prepared by admixing thefollowing materials:

Ingredient: Amount Acetaldehyde 20.0 Isobutyraldehyde 16.0Isovaleraldehyde 40.0 Methyl sulfide 0.35 Methyl disulfide 0.44 Isobutylacetate 0.12 Isoamyl acetate 0.20 Phenylethyl acetate 0.59 Diacetyl 0.02Acetophenone 1.00 Furfural (50%) 0.06 Benzaldehyde 1.00Phenylacetaldehyde 0.58 Isoamyl alcohol 0.18 Phenylethyl alcohol 3.50'y-Butyrolactone 0.13

A nut-like flavor note material is prepared by combining the followingingredients as shown:

Ingredient: Amount (parts) Material produced in Example I 11.0 Materialproduced in Example II 27.0 Material produced in Example III 20.0

A first flavor composition is prepared by a 1.2% dilution of the basiccocoa flavor in propylene glycol/ethyl alcohol (v./v. 80/20). Vanillinis added in the ratio of 250 mg. per kilogram of solution. A secondflavor composition is prepared by a 2% dilution of the basic cocoaflavor combined with the nut-like flavor note material (weight ratio84.2:58.0) in propylene glycol/ethyl alcohol (v./v. 80/20). Vanillin isadded in the ratio of 250 mg. per kilogram of liquid.

The combined flavor (2% dilution) thus prepared is found to have anexcellent cocoa flavor and aroma note, whereas the flavor without thetricyclic pyrazines of this invention lacks the desirable nut-likeflavor note.

Example V The pyrazine-containing flavor note material of Example IV isadded to a commercially available chocolate flavored dessert containingskim milk, sugar, non-fat dry milk solids, and cocoa with a bland, thiscocoa flavor. The addition of 63 mg./kg. increases the nut-like note toa desirable level and improves the overall flavor.

It will be appreciated from this disclosure that otheralkyl-substitutedand unsubstituted tricyclic pyrazines can be used in lieu of or additionto the materials shown above with favorable results.

Example VI A flavor composition according to this invention is preparedby combining the following materials as shown:

Compound: Amount (grams) Tricyclic pyrazine of Example I Tricyclicpyrazine of Example II l5 Tricyclic pyrazine of Example III 12 Thistricyclic pyrazine composition is added to a chocolate milk having abland, thin cocoa flavor. Adding mg./kg. increases the nut-like note,and supplemental addition of mg./kg. of the basic cocoa flavor materialas described in Example IV gives the chocolate milk an excellent cocoaflavor and aroma note.

12 Example VII A commercial cocoa mix is used to prepare two differentbatches of beverage. The first batch is evaluated Without any furtheradditive, while the material of Example I is added to the second batchin the ratio of 40 mg. of the tricyclic pyrazine to each kilogram ofcocoa beverage. The beverage without tricyclic pyrazine gives a ratherharsh flavor impression, while the beverage containing tricyclicpyrazine according to the present invention has a fuller, richer cocoaflavor.

Example VIII The aroma provided by the1,2,3,4,6,7,8,9-octahydrophenazine (as produced in Example II) in thecomposition set forth below is important to the natural undertonequality of the certain floral absolutes such as Hyacinth and Narcissus.The formulation is as follows:

Ingredient: Amount Phenylacetylaldehyde 150 Tolubalsamol 50Phenylethylalcohol 150 Cinnamyl alcohol from Styrax 200Hydroxycitronellal Heliotropin 50 Terpineol 30 Petitgrain bigarade 40Benzylacetate over Jasmin 150 Benzylacetate, extra Benzylbutyrate 10Linalool, extra 100 Hyacinth absolute 10 Benzylacetate 10Cinnamylacetate 30 Phenylethylacetate 20 a-Ionone 20 Isoeugenol, extra 5Jasmin absolute 10 Rose de Mai absolute 10 Neroli, extra 10'y-n-Methylionone 15 Phenylethylalcohol Jasmin chassis absolute 5Eugenol 3 1,2,3,4,6,7,8,9-octahydrophenazine 1 The addition of the1,2,3,4,6,7,8,9-octahydrophenazine lends an authentic, earthy, dankcharacter bringing the composition closer to the odor of pure Hyacinthabsolute.

Example IX A perfume composition is prepared by admixing the followingingredients:

Ingredient: Amount Guaiac wood oil 40 8,9-epoxycedrane 2O Octahydro3,6,8,8 tetramethyl-lH-3a,7-methanoazulen-6-yl ketone (Cedryl methylketone 6 Methyl 3,6,7,8 tetramethyl 1H,3a,7-methanoazulen-G-yl ketone=(Cedry methyl ketone) 6 Ortho-t-butylcyclohexanol 3 1,2,3,4,6,7,8,9octahydrophenazine (10% solution in 95% ethanol) 1 13 wherein two orthree of the dashed lines represent nonallenic double bonds; m and n aredifferent integers from one to six, inclusive, and the sum of m and nisnot greater than eight; and R R R R R R R and R are hydrogen or loweralkyl.

2. A tricyclic pyrazine according to claim 1 wherein there are threedouble bonds in the heterocyclic ring; m is one; n is two; R is a methylsubstituent on a carbon atom adjacent to the heterocyciic ring; and R RR R R R and R are hydrogen.

3. A tricyclic pyrazine according to claim 1 wherein there are threedouble bonds in the heterocyclic ring;

14 m is six; n is two; and R R R R R R R and R are hydrogen.

References Cited UNITED STATES PATENTS 3,453,365 7/1969 Lane et al260-250 R 3,471,492 10/1969 Johnston 260-250 R NICHOLAS S. RIZZO,Primary Examiner US. Cl. X.R.

P0-1050 UNITED STATES PATENT OFFICE FQ v (5 69 ceemrmwr or (JGRREQTEQNPateot No. 3,705,121 Dated 12/5/72 Inventor) ALAN O. PITTET et al I Itis certified that error appears in the above-identified patent and thatsaid Letters Patent-arehereby corrected as shown below:

. I v i r- Col. 2 line 7, correct "the spelling of "hydrocarbon" Col. 2,line 18, after "4" and before "6" eancel -5--.

Col. 11, line 53, change "this" to'thi Col.'.l2, line 58, strike'-'(ced'ry1 methyl ketone)6"" I end insert in lieu thereof -(cedrenol)...20

Signed ami sealed this 8th day of May-19.73. Y

(SEAL) Attest:

EDWARD MFLETCHEBJR. i ROBERT GOTTSCHALK Artesting Officer Commissionerof Patents

